A genetic analysis of the Australian dingo suggests the dogs tagged along on an epic expansion of people out of southern China around 6,000 years ago. An international team claims that dingoes descend from a small group that could have been introduced to Australia in a "single chance event" from Asia.

Evidence from mitochondrial DNA suggests that the wild dogs arrived on the continent around 5,000 years ago.

The work appears in Proceedings of the National Academy of Sciences.

Peter Savolainen of the Royal Institute of Technology in Stockholm, Sweden, and colleagues think the introduction of the dogs may be associated with the spread of seafaring Austronesian-speaking people throughout South-East Asia.

The Austronesian culture had its origins in south China, expanding from Taiwan via the Philippines to Indonesia.

Although dingoes are now wild, they descend from domestic dogs that accompanied these Austronesians on their voyages.

Family tree

The new data comes from an analysis of dingo, dog and wolf mitochondrial DNA (mtDNA) types. This is the DNA found in the cell's "power houses", and it is passed down from parent to offspring on the maternal side only.

On a family tree of mtDNA types in different members of the dog family shows that dingoes sit on a major branch of this tree alongside 70% of domestic dog sequences.

All the dingo mtDNA types either belonged to or showed great similarity to a single type called A29.

DNA links dingoes to an expansion out of southern China

Studies of dingo physiques suggest they are very similar to Indian pariah dogs and wolves. This has led some researchers to propose that seafaring peoples from India may have introduced them to Australia.

But among domestic dogs, A29 is found only in East Asia, suggesting the dogs' origins lie here, rather than on the Indian subcontinent. The researchers analysed mtDNA sequences in 211 dingoes and compared them to a world-wide sample of 676 dogs.

When Europeans arrived in Australia, the dingo was widespread, living mostly as a wild animal. However, some Aboriginal groups kept them as pets or as hunting dogs.

The dogs only failed to reach Tasmania because rising sea levels had inundated the Bass Strait some 6,000 years earlier.

The dingo is not endangered but interbreeding with domestic dogs is a major problem. About 80% of dingoes are now thought to be hybrids.

Dingoes are most common along the edges of forests and grasslands where prey is usually abundant. They live on small mammals, especially rabbits, but also feed on kangaroos, lizards and carrion.

The dingo has been implicated in driving the now extinct Tasmanian "tiger" - or thylacine - off mainland Australia, and marginalising it in its final island habitat.

All of the hundreds of breeds of modern domestic dog, from the Afghan hound to the chihuahua, can be traced back to just 10 "progenitor" breeds, say US scientists... Humans first domesticated wolves about 15,000 years ago, most probably to help them hunt. Domestication involves selectively breeding a species so that they can be controlled more easily. The latest genetic information suggests that the domestication of wolves first occurred in Asia... The researchers believe that by 10,000 to 12,000 years later, 10 "progenitor breeds" of dog had been created to fulfill different roles alongside their masters... The 10 progenitors identified by the researchers are: sight hounds, scent hounds, working and guard dogs, northern breeds, flushing spaniels, water spaniels and retrievers, pointers, terriers, herding dogs and toy and companion dogs... Gordon Lark, who is studying canine genetics at the University of Utah... says developing a genetic map, rather than a genealogical one will be more useful for understanding canine evolution, behaviour and health. Scientists are expected to finish sequencing the dog genome within a year.

They forgot "chow hounds" -- probably the first use of dog species. As Dustin Hoffman's character sez in "Little Big Man", the flavor can be downright delicate.

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